The present invention relates to a method and an apparatus for cleaning the inside of a narrow channel or channel of a medical instrument such as an endoscope, a surgical instrument, and the like. More particularly, the present invention relates to a method and an apparatus for reliably removing materials such as mucus, blood, and the like which have adhered to the inner surface of the channel.
The use of endoscopes has spread rapidly and widely in the medical field, and endoscopic operations are performed frequently. However, with the increasing number of endoscopic examinations being performed in recent years, infections are on the rise. Insufficiently cleaned endoscopes cause most of these infections.
A large number of medical instruments for use in conjunction with endoscopes have been developed. Many of these medical instruments have complicated configurations, such as coil-shaped long, narrow tubes, that are difficult to clean. Infections due to insufficient cleaning of these instruments are on the rise and have become a significant problem. Thus, there is a great demand for the development of methods of preventing infections from occurring at the time of examination and treatment.
The preparatory step in cleaning the endoscope involves removal of mucus and blood (materials composed of mainly protein and fatty components) with a diluted solution of detergent containing an enzyme that decomposes fat and protein. This preparatory cleaning step should be performed before performing the subsequent operation of sterilizing the endoscope.
There are many imperfections on the inner surfaces of the channels of endoscopes through which bioptic and/or other instruments pass. Organic matter may adhere to these flaws, leading to the growth of bacteria and subsequent infection of patients. Additionally, such contaminants adhere to the inner surfaces of suction channels. Further, there is a possibility that bacteria will penetrate into a cavity or imperfection at the location where tubes or channels are interconnected, or on the inner surface of such tubes. Thus, it has become accepted and viewed as essential to clean the interiors of the various channels of the medical instrument with a cleaning brush.
Current practice involves manually cleaning channels of medical instruments such as endoscopes with a cleaning brush that is exclusively used for that purpose, while allowing water to flow into the channels (e.g., the clamp channel and the suction channel). Repeated brushing/scrubbing operations are necessary. Unfortunately it is possible for the tip of the cleaning brush to rub contaminants into the inner surface of the clamp channel and the suction channel after it is separated from the cleaning brush. Furthermore, it is difficult for running water to flow smoothly through the channels. As a result, the water cannot carry away the contaminants. In addition, the tip of the cleaning brush can damage the inner surface of the clamp channel and the suction channel to form cavities or irregularities, whereby bacteria or viruses can enter the cavities and become entrapped. This is also a problem. Commercially available cleaning brushes are much larger than bacteria and viruses. Thus, it is impossible for the cleaning brush to remove pathogenic bacteria which have entered into a fine flaw or cavity inside the channel.
Many cleaning devices for cleaning medical instruments, such as endoscopes, by using ultrasonic waves have been proposed. However, these cleaning devices are used to clean the outer surface of the medical appliance and cannot clean the internal, narrow channels.
The high cost of endoscopes precludes hospitals and other medical establishments from having many of them. Accordingly, to use the endoscope safely and efficiently, there is a demand for the development of a method and an apparatus capable of accomplishing effective cleaning of the inside of a channel of an endoscope or other medical instrument in a relatively short period of time.
There is a limitation in the method of injecting chemicals commercially available into each channel of the endoscope and manually brushing the inner surface of each channel with a cleaning brush. As a result, after an incomplete cleaning is performed, a non-sterile endoscope may be used on patients.
The present invention provides a method and an apparatus capable of easily and reliably cleaning the inside of a channel of a medical appliance (instrument) such an endoscope.
In one aspect, the invention provides a method for cleaning the inside of a channel of a medical instrument comprising the steps of:
inserting a cleaning catheter having an ultrasonic vibrator mounted thereon into a channel of said medical instrument; and
vibrating said ultrasonic vibrator and moving said cleaning catheter in said channel to transmit an ultrasonic vibration to an inner surface of said channel, whereby said ultrasonic vibration induces undesirable matter disposed the inner surface of said channel to separate from said inner surface.
In another aspect, the invention provides a cleaning apparatus for cleaning an inside of a channel of a medical instrument, comprising:
a cleaning catheter that comprises an ultrasonic vibrator that can be inserted into said channel; and
an ultrasonic oscillator for operating said ultrasonic vibrator.
In yet another aspect, the invention provides a method for cleaning an interior surface of a channel of a medical instrument, comprising the steps of:
inserting into said channel a cleaning catheter comprising an ultrasonic vibrator, with a cleaning liquid-feeding tube surrounding said cleaning catheter, said ultrasonic vibrator being exposed into said channel of said medical instrument;
expelling cleaning liquid from a gap between said cleaning catheter and said cleaning liquid-feeding tube; and
operating said ultrasonic vibrator to cause ultrasonic vibrations to impinge upon the inside of said channel, whereby undesirable matter is separated from an inner surface of said channel by said ultrasonic vibrations and transported through said channel by said cleaning liquid.
In another aspect, the invention provides a cleaning apparatus for cleaning the interior of a channel of a medical instrument, comprising:
an ultrasonic cleaning device comprising a cleaning catheter including an ultrasonic vibrator;
an ultrasonic oscillator for operating said ultrasonic vibrator; and
a cleaning liquid discharge device comprising a cleaning liquid-feeding tube into which said cleaning catheter can be inserted with said ultrasonic vibrator exposed, a cleaning liquid discharge port, a cleaning liquid storage tank and a pump for feeding cleaning liquid from said tank to said discharge port.